xref: /freebsd/sys/contrib/device-tree/Bindings/clock/rockchip,rv1108-cru.txt (revision d9a42747950146bf03cda7f6e25d219253f8a57a)
1* Rockchip RV1108 Clock and Reset Unit
2
3The RV1108 clock controller generates and supplies clock to various
4controllers within the SoC and also implements a reset controller for SoC
5peripherals.
6
7Required Properties:
8
9- compatible: should be "rockchip,rv1108-cru"
10- reg: physical base address of the controller and length of memory mapped
11  region.
12- #clock-cells: should be 1.
13- #reset-cells: should be 1.
14
15Optional Properties:
16
17- rockchip,grf: phandle to the syscon managing the "general register files"
18  If missing pll rates are not changeable, due to the missing pll lock status.
19
20Each clock is assigned an identifier and client nodes can use this identifier
21to specify the clock which they consume. All available clocks are defined as
22preprocessor macros in the dt-bindings/clock/rv1108-cru.h headers and can be
23used in device tree sources. Similar macros exist for the reset sources in
24these files.
25
26External clocks:
27
28There are several clocks that are generated outside the SoC. It is expected
29that they are defined using standard clock bindings with following
30clock-output-names:
31 - "xin24m" - crystal input - required,
32 - "ext_vip" - external VIP clock - optional
33 - "ext_i2s" - external I2S clock - optional
34 - "ext_gmac" - external GMAC clock - optional
35 - "hdmiphy" - external clock input derived from HDMI PHY - optional
36 - "usbphy" - external clock input derived from USB PHY - optional
37
38Example: Clock controller node:
39
40	cru: cru@20200000 {
41		compatible = "rockchip,rv1108-cru";
42		reg = <0x20200000 0x1000>;
43		rockchip,grf = <&grf>;
44
45		#clock-cells = <1>;
46		#reset-cells = <1>;
47	};
48
49Example: UART controller node that consumes the clock generated by the clock
50  controller:
51
52	uart0: serial@10230000 {
53		compatible = "rockchip,rv1108-uart", "snps,dw-apb-uart";
54		reg = <0x10230000 0x100>;
55		interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>;
56		reg-shift = <2>;
57		reg-io-width = <4>;
58		clocks = <&cru SCLK_UART0>;
59	};
60